Method and apparatus for refrigerating



April 14, 1931.. L KNQX 1,800,258

METHOD AND APPARATUS FOR REFRIGERATING Filed Sept. 22, 1926l 2 Sheets-Sheet 1 lNVENTOR page WW2 April 14, 1931;

L. Lf KNOX 1,800,258

METHOD AND APPARATUS FOR REFRIGERATING r-iied sept. 22, 1926 2 Sheets-Sheet 2 `Patented Apr. 14, 1931 l* UNITED vsTaTEs PATENT OFFICE LUTHER L. KNOX, 0F BELLEVUE PENNSYLVANIA, ASSIGNOB TO KNOX PRODUCTS COMPANY, OF PITTSBURGH, PENNSYLVANIA.' A CORPORATION 0F PENNSYLVANIA METHOD AND APPARATUS FOB BEFBIGERATING Application nled September 22, 1,928. Serial No. 138,983.

This invention relates to a method and a paratus for refrigerating, and is particular y useful in connection with mechanical refrlgeration systems wherein a refri erating me as a result kthe foo s in the compartment are rapidly dehydrated. The moisture leaves the food, and as the air circulates in the compartment it freezes on the outside of the expansion coil and .materially reduces its eificiency, in addition to reducing the quality of the food in the compartment. This reduction in efficiency is so great that it is necessary to put the unit out'of operation at regular intervals for a long enough period to rmit de-icing, that is to say, to permit o the collected 1ce melting oif the coil.

I provide for supplying a refrigeratlng medium, as for example, ammonia or methy chloride, to a heat transfer unit, circulatingl a liquid between the place or compartment to be refrigerated and the heat transfer unit, and maintaining the liquid at such temperature that the compartment or the com artment walls are maintained above the reezin point. y

ith this arrangement the food is not dehydrated, and since there is no opportunity for frost forming on the expansion coils, den

icing is obviated and the unit may be operated continuously.

Preferably, my invention will be embodied in an insulated cabinet having a compartment therein, this compartment being double-walled to permit of circulating the liquid. The space between the double walls and above the compartment comprises a container for the liquid, and the heat transfer unit will preferabli be placed in the top of this container. will be seen that ordinary water might be used, since it is intended to maintain the liquid above the freezing oint, but I lpreferably em loy a solution o a salt such as calcium ch oride. The calcium chloride may be placed in a permeable holder in the container so that the unit may be shipped dry and may then be charged with ordinary water. By this arrangement the solution is maintained saturated and the de osition of salt in the lower parts of the liqui container is eliminated.

It is customa in mechanical refrigeration systems to provide for the freezing of water in small pans so as to' rovide ice cubes for consumption. I provi e a special compartment cooled by the heat transfer unit roper, while the main compartment is cooled t rough the liquid medium.

Certain foods, notably butter, will acquire the odor of other foods in the refrigerator, and I therefore provide a plurality of compartments which are substantially isolated from one another. The several compartments may be portions of a single large compartment, and referabl a single door is employed. Yiel able paclizng means are employed for cooperating with the partitions between the compartments for closing them off from one another. This has been found in actual practice to prevent air circulation through the refrigerator and consequent acquisition of food odors by other substances in the same refrigerator. In order to make a more sanitary refri erator I may employ removable liners for t e several portions of the compartment.

In the accompanying drawings, which illustrate a preferred form of the invention as applied to a household refrigerator- Figure l is a vertical section through a refrigerator taken on the line I--I of Figure 2;

Figure 2 is a vertical section taken on the line II-II of Figure 1;

Figure 3 is a horizontal section taken on the line III- III of Figure 1;

Figure 4: is a perspective view, partly in section,l showing the food compartment and the liquid container; and

Figure 5 is a vertical section through a modified form of food compartment showing the use of liners for the several compmtment partitions.

In the illustrated embodiment ofthe invention there is shown a refrigerator comprising an outer shell 2, in the lower portion 3 of which there'is placed-fi compressor and associated mechanism for handling a refrigeratin medium such as ammonia or methyl chlori e.v The upper portion of the shell 2 forms the refrigerator proper, and it has a food compartment indicated generally by the reference character 4. This foodcompartment is shown in more detail in Figure 4. It comprises a bottom 5, a back wall 6, side walls 7 and a top wall 8. Extending upwardly from the top 8 is a box-like container, indicated generally by the reference character 9. The container 9 is larger than the compartment 4, thus forming, in effect, a double-walled structure adapted to receive a liquid 10.

As best shown in Figure 2,-the container-9 is substantially filled with liquid, preferably a calcium chloride solution.- The container extends almost to the top of the'refrigerator and is provided with a top 11. An insulating cover 12 forms the top of the unit.

A heat transfer unit, indicated generally by the reference character 13, is mounted in the upper portion of the container 9. This unit is connected to the compressor and associated apparatus mounted in the compartment 3, so that the refrigerating medium is circulated through the heat transfer unit 13. The particular form of compressor mechanism forms no part of the present invention.

AI have therefore lonly indicated portions thereof by dotted lines in Figure 2.o There is shown a motor 14 connected to a compresso;` 15 and provided with a speed-regulating rheostat 16 whereby the operation of the apparatus may be varied as'desired.

In operation, the li uid 10 circulates 1n the space between the wal s of the food com art ment 4 and the container9, thus maintaining the food compartment at reduced temperature. The temperature maintained in the food vcompartment may be varied. by adjusting the rheostat 16.

As above stated, it is preferred to use a calcium chloride solution in the container 9, and I therefore provide a permeable holder, such as a fabric bag 17, in the container 9. This ba is filledwith a mixture of calcium chlori e and lime, so that the unit may be shipped dry and merely filled with vwater to put it in condition for operation. The 'use of the bag insures that a proper solution will be maintained and that no salt will accumulate in the bottom of the container. p

The food compartment 4 is, of course, provided with a door 18, as shown. The compartment is provided with shelves which may be the wire gratin s' ordinarily employed. but which are pre erably metal partitions 19 which divide the compartment 4 into isolated partitions. Yieldable acking members 20 are provided on the oor 18. These'packing members cooperate with the edges of the partitions 19 to substantially seal of the com artment portions one from the other and t us prevent air circulation within the refrigerator. This is found to be of great value in eliminating the acquiring of certain food odors by other foods in the refrigerating com artmen-t 4. Further packings 21 are provi ed on the outer ortions o the door 18 for sealing off the food compartment from the exterior.

It may be desirable to maintain the different individual compartment portions at different temperatures, and this may be accomplished by shaping the liquid container 9 as shown in Figures 2 and 4. Instead of the container being of uniform width from top -to bottom, t-he side ortions thereof are tapered so that at the ottom of the food compartment 4 a smaller area for heat transfer between the food compartment and the cooling medium is afforded than in the upper portions of the food compartment. In this manner the various compartment portions, or individual compartments as they may be termed, may be maintained at differf ent relative temperatures.

In o rder to form ice cubes, the heat transfer unlt 13 is provided with a supplemental coil 22 within which drawers 23 may be placed. These drawers are of the usual form, havingv ockets which may be filled with water to e frozen into cubes of ice. The coils 22v are not immersed in the. solution 10, as a artition 24 is provided for isolating them rom the contamer 9. The partition 24 forms a compartment 25, and it will be noted from Figure 2 that the door 18 is effective for closing oif this compartment, as well as the main food compartment 4.

`For sanitarv reasons it is desirable to have a glass-like finish on the interior of the food compartment, and in Figure 5 I show a way in which this object may be inexpensively attained. In this form of the invention parts corresponding to similar parts already described are given the same reference character with an a suiixed thereto. Each of the compartment rportions into which the food compartment 4 is'divided by partitions 19 is supplied with a metal liner 26. This may be formed from enameled metal and put into lace. Each liner has flanges 27 and the anBges of adjacent liners overlap, as shown 1n these iianges 27 and thus isolate the com artment portions from one another. The lmers may be held in place in any desired manner, an if theybecome chipped they are readily replaceable.

I have illustrated and described a pre.-l

igure 5. The packings 20 bear against ferred embodiment of the invention, but it will be understood that it is not limited to the 1,soo,ass 3 following claims.

(ment, and means for supplyin 1. A refrigerator comprising a plurality of open sided compartments, a door for closing the open sides of the compartments, and packing strips cooperating with the door and the edges of the compartments for substantially isolating the compartments from` one another. t

2. wA refrigerator comprising an o en sided compartment divided into portions y partitions, a door for closing the open side of the compartment, packing strips cooperating with the door and the partitions for substantially isolating the compartment portions from one another, and liners for the mdividual compartment portions.

3. A refrigerator comprising a compartment, a partition dividing the compartment into isolated portions and means for supplying a cooling medium to the Walls of the compartment, the last mentioned means having a gradually varying dimension whereby it is effective for Ycooling different compartments in different amounts.

4. A refrigerator comprising a comparta cooling medium to the walls thereof, t e portions of the walls which are exposed to the cooling medium decreasing in area from top to bottom of the compartment.

5. A refrigerator comprising an insulated compartment, non-insulating partitions dividing the, compartment into substantially isolated portions, and removable liners for the indivldual portions.

6. A refrigerator comprising a compartment, a jacket therefor extending above the compartment and adapted to hold a liquid, a heat transfer unit' in the jacket above the compartment and a freezing compartment adapted for direct-cooling by the heat transfer unit.

transfer unit and another of said compartments.

10. The method of refrigeration which comprises supplfying a refrigerating medium to a heat trans er unit, circulating a liquid between the place to be refrigerated and the heat-transfer unit, and va ng the area of the place to be refrigerate exposed to the liquid in accordance with the distance from the heat transfer unit.

In testimony whereof I have hereunto set my hand.

LUTHER L. KNOX.

7. A refrigerator comprising a comparti ment, a jacket therefor extendlng above the compartment and adapted to hol a liquid a heattransfer unit in the jacket above t e compartment, a freezing compartment adapted for direct cooling by the heat transfer unit, and a common door forclosing the first mentioned compartment and the freezing compartment.

8. A refrigerator comprising a compartment, a jacket for the walls thereof, said jacket decreasing in width in the general direction of the compartment walls from top to bottom thereof and means for supplying a cooling iiuid to the jacket.

9. A refrigerator comprising a heat transfer unit, a plurality of compartments, at

y least one of said compartments being cooled directly b the heat transfer unit, and means for circ a liquid between the heat 

